This honestly sounds like someone doesn't know what hoops auto manufacturers have to jump through under CAFE and how the govt regulates fuel and oil recommendations under same.
Recommended Synthetic OIL
- Thread starter HillsAreFun
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
This honestly sounds like someone doesn't know what hoops auto manufacturers have to jump through under CAFE and how the govt regulates fuel and oil recommendations under same.
1) As mentioned, analyis has shown the 40 weight is closer to 30.
2) All oils are not thin enough when cold so the question is, why wouldn't you go as thin at the cold end as possible? Am I missing something? Unless of course you consume too much then I'm down with the Rotella or the Mobil 1 Diesel formula. But I don't understand why we would want a thicker oil at startup. The quicker that stuff gets up there and is suited to temp the better right?
3) In my BMW, they only put three oils in (that conform to European 15k spec) and the Mobil 1 0w-40 is one. BTW, I'm a Toyota guy so don't hold that BMW thing against me. Serious. I'm just saying that there really are very few 15k oils in this market.
2) All oils are not thin enough when cold so the question is, why wouldn't you go as thin at the cold end as possible? Am I missing something? Unless of course you consume too much then I'm down with the Rotella or the Mobil 1 Diesel formula. But I don't understand why we would want a thicker oil at startup. The quicker that stuff gets up there and is suited to temp the better right?
3) In my BMW, they only put three oils in (that conform to European 15k spec) and the Mobil 1 0w-40 is one. BTW, I'm a Toyota guy so don't hold that BMW thing against me. Serious. I'm just saying that there really are very few 15k oils in this market.
0w40 
Our engines are very easy on oil, so it doesn't really matter what you put in
Based on my oil sample, Blackstone suggested I stretch my intervals to 12,000 miles.
For my next sample, I pushed it to 19,xxx miles and they said it still had plenty of life left.
That was with conventional Toyo 10w-30 (bottled by Exxon/Mobil)
Now, I typically do frequent changes every 5000 miles because I'm OCD like that about my maintenance, but I do push the intervals beyond 12k for oil samples as the results tells you more with old oil than with fresh oil
Everyone has their own opinion on which oil they prefer, so I won't even get into that, but my only suggestion is to choose one brand and stick with it for the life of the engine
Reason?
Different brands have different cleaning agents and additives that don't always play well together, sometimes creating sludge
After sticking with one brand, my lab results got better and better over the years
I also don't like the idea of switching to synthetic on a worn motor
(I have my reasons)I'm sure every gear head wants to put in what they feel is best and that's fine, but conventional works just fine for my pocket and my motor
Funny thing, I was in a hurry to get out town and didn't have time to change my own oil. I took it down a Mobil1 express lube shop (I general trust them as they maintained my BMW). Did think much about it, hopped in the truck at started off down the highway. Looking up at the little sticker they put on the window, they used M1 syn 0-50w. Truck was happy and ran great. But never could find that oil in the stores. I know cool story huh.0w40
Yeah 0w50 and 0w60 are manufacture specific, the 0w40 is hard to find but can be found in big box stores on occassion. I used it in my GT-R, and I like having just 1 type of oil at the house so I started using it in everything as like has been explained in the thread oil has come a long way in the last 20 years.
I agree with Snakeeater on the intervals. I still change mine after a year and probably don't need to. I know that our engines are easy on oil. Go peruse the reports on BobIsTheOilGuy.com and this motor exhibits dramatically less wear than anything I've seen.
From reading the Oil University stuff on BITOG, I do believe that the lower the first number, the better. That is, the bulk of our wear occurs at startup so unless you're experience lots of consumption, why not the lower the better? The "40" or second number in my case is actually closer to "30" for Mobil 1 0w-40 from all accounts. But what do I know?
Anyway, I attached my Blackstone I got today. I change it once a year. Period. I didn't get them the first 3 or 4 years but it sure is looking good now.
From reading the Oil University stuff on BITOG, I do believe that the lower the first number, the better. That is, the bulk of our wear occurs at startup so unless you're experience lots of consumption, why not the lower the better? The "40" or second number in my case is actually closer to "30" for Mobil 1 0w-40 from all accounts. But what do I know?
Anyway, I attached my Blackstone I got today. I change it once a year. Period. I didn't get them the first 3 or 4 years but it sure is looking good now.
Last edited:
Just figured I'd post some numbers. I have been running Mobil 1 0w40 for 1 yr since I got the vehicle. Engine has 125k miles, and i ran oil pressures today at oil pressure sending unit site. With warm engine and idle at 650 had 19 psi (FSM recs >4.3), at 3000 rpm had pressure of 69 psi (FSM recs 36-71). Seems to be pretty good. Just wanted to share. Not sure if there is any concern of being over 71 -guess I'm close.
It is, it's also true. I live in a hot climate with little risk of freezing. Thicker oil will always be my preference. The oil pressure gauge agrees.
I respectfully disagree.
In our 1HD's there is a big difference in the oils they use up in Hokkaido as to what we us down here. Also, they tend to use thicker oils down in Aus as well. I had always used 40 weight but am trying a designer race 50 weight right now. Interestingly, the truck is a Hokkaido vehicle and spent the majority of its time with 10w-30 in it.
Since my engine rebuild I've been using Mobil 1 5w30.
No issues yet
No issues yet
I bought my rig with 150K on the clock. It had been running with dino 5w-30 all its life. I thought I was doing the right thing about switching to Mobil 1 10w-40 Hi-Mileage. Synthetic is better, right?
I ran that Mobil synthetic for a few years. Did a few Blackstone analyses and got really good wear numbers. Over time though the engine started leaking like a sieve. I fixed most of the leaks but was having issues with the upper oil pan and I was concerned more leaks were going to pop up. Plus, having to add about a quart of relatively expensive synthetic oil every 1000 miles was getting annoying. The upside is that I always have fresh oil in there!
Curious to see if switching oil might help, I switched back to dino (Shell Rotella 15w-40 to be exact). The upper oil pan leak practically stopped. The oil looks really good in it even after 9 months. Oil analysis also shows good wear numbers.
I've thought about switching to the Shell Rotella synthetic 5w-40. Not sure why I would though since the 15w-40 works well for me, I don't have leaks and it is reasonably priced.
Keep in mind I live in a temperate to warm climate, only put about 5K miles per year on the truck, and regardless of weather I am religious about letting my truck warm up before going anywhere. I drive very gently until truck is at full operating temp. I change my oil and filter once a year unless preparing for (or coming back from) a very demanding overland trip.
Run what works for your truck, your environment and your piece of mind. Cheers!
I ran that Mobil synthetic for a few years. Did a few Blackstone analyses and got really good wear numbers. Over time though the engine started leaking like a sieve. I fixed most of the leaks but was having issues with the upper oil pan and I was concerned more leaks were going to pop up. Plus, having to add about a quart of relatively expensive synthetic oil every 1000 miles was getting annoying. The upside is that I always have fresh oil in there!
Curious to see if switching oil might help, I switched back to dino (Shell Rotella 15w-40 to be exact). The upper oil pan leak practically stopped. The oil looks really good in it even after 9 months. Oil analysis also shows good wear numbers.
I've thought about switching to the Shell Rotella synthetic 5w-40. Not sure why I would though since the 15w-40 works well for me, I don't have leaks and it is reasonably priced.
Keep in mind I live in a temperate to warm climate, only put about 5K miles per year on the truck, and regardless of weather I am religious about letting my truck warm up before going anywhere. I drive very gently until truck is at full operating temp. I change my oil and filter once a year unless preparing for (or coming back from) a very demanding overland trip.
Run what works for your truck, your environment and your piece of mind. Cheers!
Sheesh, I put on 5000 miles in three weeks
LOL. I only use the rig for wheeling and back country trips...and, I don't get out nearly as much as I'd like.
I picked up some Mobil1 0w40 synthetic 5 quart jugs on Amazon for 22 and change with Prime shipping. They seem to move the price around a lot so best to set up a CamelCamel watch on the product.
Thanks! Just ordered 4, maybe I should get more.
regarding the use if diesel oil, I did a little research and found this.
Diesel engine oils have a higher anti-wear (AW) load in the form of zinc dialkyldithiophosphate (ZDDP). The catalytic converters in diesel systems are designed to be able to deal with this problem, while the gasoline systems are not. This is one of the main reasons you don’t want to use a diesel engine oil in your gasoline engine.
Last edited: